【摘要】 提出了信号预滤波结合阈值自学习小波去噪的综合滤波方法。该法通过对恒定状态下带噪压力信号阈值自学习使得重构信号与期望输出均方误差最小来获得单一工况下的最佳去噪阈值,再将此阈值用于同一工况下整个时间段信号的去噪,不同工况下得到不同的最佳阈值进而获得最优输出。数值计算对比证明,该方法对噪声抑制作用明显,比传统小波去噪、改进神经网络去噪等方法效果更好。更多还原

【Abstract】 Pre-filter combined with threshold self-learning wavelet algorithm is proposed for pressure signal denoising.Firstly,the denoising threshold is self-learnt in the steady flow state,and then it is modified on a given limit to make the mean square errors between reconstruction signals and desirable minimal outputs,thus the corresponsive optimal denoising threshold in a single operating case can be obtained.These optimal thresholds are used for the whole signal denoising and different optimal thresholds are obtained in various cases.Simulation results and comparative studies show that the approach has an obvious effect of noise suppression.The method is superior to traditional wavelet algorithms and artificial neural networks.更多还原